Do you have any seniors to help simulate the rain effect of Baidu Weather search page with canvas? thank you very much.

canvas simulates the rain effect of Baidu weather search page


rain.png
rain.png transparent

Javascript
Jan.03,2022 
<!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8">
        <title></title>
        <style>
            *{margin: 0;padding: 0;}
            canvas{background: -sharpfff;}
        </style>
    </head>
    <body>
        <canvas id="canvas" width="500" height="800" ></canvas>
        <script>
            var can = document.getElementById("canvas");
            //
            var cxt = can.getContext("2d");
            //
            var w = can.width = window.innerWidth;
            var h = can.height = window.innerHeight;
            //
            window.onresize = function() {
                w = can.width = window.innerWidth;
                h = can.height = window.innerHeight;
            };
            //
            cxt.fillStyle = "aqua";
            
            var drops = [];
            // 
            function Drop() {}
            //
            Drop.prototype = {
                init: function() { // 
                    this.x = random(0, w);//
                    this.y = 0;//y
                    this.vy = random(4, 5); //
                    this.l = random(0.8 * h, 0.9 * h);
                    this.r = 1; //
                    this.vr = 1; //
                    //
                    this.a = 1; // =>0
                    this.va = 0.96; //
                },
                draw: function() { //
                    if (this.y > this.l) { // 
                        cxt.beginPath(); //
                        cxt.arc(this.x, this.y, this.r/4, 0, Math.PI * 2, false);
                        cxt.strokeStyle = "rgba(219,227,226," + this.a + ")";
                        cxt.stroke();
                    } else { //
                        cxt.fillStyle = "rgb(219,227,226)";
                        cxt.fillRect(this.x, this.y, 1, 10);
                    }
                    this.update();
                },
                update: function() { //
                    if (this.y < this.l) {
                        this.y += this.vy
                    } else { // 
                        if (this.a > 0.03) {
                            this.r += this.vr;
                            if (this.r > 50) {
                                this.a *= this.va;
                            }
                        } else {
                            //
                            this.init()
                        }
                    }
                }
            };
            for (var i = 0; i < 50; iPP) {
                setTimeout(function() {
                    var drop = new Drop();
                    drop.init();
                    drops.push(drop);
                }, i * 300)
            }
            function move() {
                //  
                // 
                cxt.fillStyle = "rgba(15,15,15,0.1)";
                cxt.fillRect(0, 0, w, h);
                for (var k = 0; k < drops.length; kPP) {
                    drops[k].draw();
                }
                requestAnimationFrame(move);
            }
            move();
            //
            function random(min, max) {
                return Math.random() * (max - min) + min; //min - max
            }
        </script>
    </body>
</html>

https://blog.csdn.net/zhuogan.

not a single high number

Previous: Mac successfully installed mongodb after starting the Times error as shown in the picture, has turned off PID or not, how to solve?

Next: About DB2SQL

css mysql arrays josn react html typescript webpack npm sass R objective-c .net sql-server jquery python-3.x angularjs django angular excel regex iphone ajax linux xml pandas vba spring database wordpress string wpf xcode windows bash postgresql oracle multithreading eclipse list firebase algorithm macos forms image scala visual-studio azure bootstrap spring-boot react-native python-2.7 docker performance function winforms matlab powershell apache dataframe api sqlite numpy rest shell selenium flutter dart maven loops qt swing android-studio csv express file class tensorflow sorting codeigniter perl
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b3c0fb-2c2fa.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b3c0fb-2c2fa.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Need Help?